ArticleInternal and emergency medicine2021
Effect of influenza vaccine on COVID-19 mortality: a retrospective study.
Article in Internal and emergency medicine, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 52 papers, 4 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
52 citing papers in PubMed, 4 syntheses or guidelines pooled it.
- Vaccination against influenza viruses reduces infection, not hospitalization or death, from respiratory COVID-19: A systematic review and meta-analysis.Journal of medical virology · 2024Pooled it
- Association between influenza vaccination and SARS-CoV-2 infection and its outcomes: systematic review and meta-analysis.Chinese medical journal · 2022Pooled it
- The effect of influenza vaccine in reducing the severity of clinical outcomes in patients with COVID-19: a systematic review and meta-analysis.Scientific reports · 2022Pooled it
- The Association Between Previous Influenza Vaccination and COVID-19 Infection Risk and Severity: A Systematic Review and Meta-analysis.American journal of preventive medicine · 2022Pooled it
- Effect and Tolerability of a Nutritional Supplement Based on a Synergistic Combination of β-Glucans and Selenium- and Zinc-EnrichedNutrients · 2021Trial
- Hyperamylasemia in COVID-19 patients: pancreatic involvement or secondary epiphenomenon?Internal and emergency medicine · 2025Observational
- Article
- Progress in combination vaccines and the co-administration of influenza virus and SARS-CoV-2 vaccines.Frontiers in immunology · 2025Review
- Factors associated with outcome in a national cohort of rhinovirus hospitalized patients in Brazil in 2022.Scientific reports · 2024Article
- Article
- Identifying the Risk Factors of Adverse Pregnancy Outcomes among Women with COVID-19: A Population-Based Case-Control Study in Southern Iran.Journal of caring sciences · 2024Article
- Non-specific protection against severe COVID-19 associated to typhoid fever and DTP vaccination.Heliyon · 2024Article
- Article
- Article
- Article
- Flu vaccine administration in the period before SARS-CoV-2 infection and its outcomes: An umbrella review.Preventive medicine reports · 2024Review
- Mapping trends and hotspots in research on global influenza vaccine hesitancy: A bibliometric analysis.Health science reports · 2024Article
- Influenza and COVID-19 co-infection and vaccine effectiveness against severe cases: a mathematical modeling study.Frontiers in cellular and infection microbiology · 2024Article
- A Cross-Sectional Survey of Knowledge, Attitude, and Practices Regarding Influenza Vaccination Among Jordanians Aged 18-64 Years with Chronic Diseases.Turkish journal of pharmaceutical sciences · 2023Article
- Lower risk for COVID-19 hospitalization among patients in the United States with past vaccinations for herpes zoster and tetanus, diphtheria and pertussis.Preventive medicine reports · 2023Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
13 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
It has been proposed that vaccines may exert an unspecific protective effect against infectious agents, different than expected. Coronavirus disease 2019 (COVID-19) is a pandemic infection with high mortality in older patients due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The high number of vaccinations may be one of the reasons why children show a lower susceptibility to SARS-CoV-2 infection and milder severity when compared to adults. We have designed a study aimed at investigating whether the influenza vaccine may reduce the susceptibility and severity of SARS-CoV-2 infection. We retrospectively enrolled 635 patients who accessed our Emergency Department from March 1st to June 30th, 2020, and were diagnosed with COVID-19 infection confirmed by an RT-PCR on an oropharyngeal swab. Clinical data, outcomes, and influenza vaccination status were collected from the electronic medical records of our Hospital. We also used data from the Italian Health Ministry to compare the prevalence of flu vaccination among the general population of the Lazio Region and our enrolled patients. We then compared clinical outcomes between vaccinated and non-vaccinated patients, by univariate and multivariate analysis. COVID-19-positive patients older than 65 years reported a lower prevalence of flu vaccination when compared to the general population residing in the Lazio (p = 0.004). After correction for gender, age, and comorbidities, we found a lower risk of death at 60 days in patients with flu vaccination than in not vaccinated patients (p = 0.001). Our study shows that flu vaccination could reduce the mortality of COVID-19. Prospective studies are needed to confirm this result.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.